DANBURY -- It could take 30 to 45 days before federal investigators determine the cause of Thursday night's single-engine plane crash near Danbury Municipal Airport.

The plane, a 1984 Beechcraft Bonanza registered to Lionel G. Brown, of Newtown, flew past the runway and crashed into 10 feet of swamp water off Miry Brook Road.

Brown, who was identified by officials as the pilot Friday, was not injured in the mishap. No one else was on board the plane at the time of the accident.

On Friday, a crane hoisted the plane out of its swampy resting place about one-quarter mile south of the airport. The plane was then taken to a hangar at Danbury airport for investigation by the National Transportation Safety Board.

Although the NTSB does not issue time lines for its investigations, Mayor Mark Boughton said Friday that "30 to 45 days is pretty standard" based on his experience.

"The only time they do anything quicker is when the answer is obvious, like the pilot ran out of gas, or something like that," Boughton said.

Officials said Brown safely climbed out of the cockpit after the crash and called 911 for help. In the wake of the crash, Brown did not volunteer exactly what went wrong to rescuers, officials said.

"As we understand it, whatever trouble the plane had happened just before it landed, and there was no time to get out a distress signal," Bernie Meehan, Danbury's assistant fire chief, said Thursday night at the scene.

"Any plane crash you walk away from is a good one. He had his seat belt on and he knew what he was doing and he was able to walk away uninjured."